The IEC 61850 standard is a set of open protocols based on Ethernet communications commonly used in electrical utilities. SCADA systems use IEC 61850 to communicate between a master station, remote terminal units (RTUs), and intelligent electronic devices (IEDs). Real-time targets may be programmed as IEC 61850 outstation devices with advanced functionality such as power quality monitoring, phasor measurement, and other analysis related to the smart grid. The DNP3 protocol has been historically used in these types of applications. It is a simpler protocol more like Modbus, and engineers are replacing it with IEC 61850 and, to a lesser extent, IEC 60870-5.
Learn how engineers are using NI in smart grid applications.
PROFIBUS (Process Field Bus)
PROFIBUS was initially created by Siemens and is now managed by PROFIBUS International. The physical layer for PROFIBUS DP is based on RS485, and this sets the standards for the number of slaves, which can be as many as 124.
See an overview of the PROFIBUS protocol.
Serial covers RS232, RS485, and RS422. Often used for instrument control, RS232 can cover distances up to 50 ft. RS422 implements differential communication, which provides longer communication distances and greater noise immunity. RS485 is a superset of RS422 that increases the number of slave devices from 10 to 32.
See all the serial interfaces for embedded systems
TCP/IP (Transmission Control Protocol/Internet Protocol)
The Transmission Control Protocol (TCP) is a reliable point-to-point communication protocol; data is delivered in an ordered, lossless manner. It is a connection-based protocol, which means that a connection between the client and the server must be established before transferring data.
Read the “Basic TCP/IP Communication in LabVIEW” white paper to get started.
UDP (User Datagram Protocol)
The User Datagram Protocol (UDP) is a transport layer protocol used in low-latency and loss-tolerating connections between devices or applications.
Learn more about the use of the protocol in the “UDP Communication in LabVIEW” tutorial.